patarol Posted December 29, 2007 Report Share Posted December 29, 2007 See my mods below, i want som more power and thinking of a 4mill crank. and cubs. there is no one that do port work hrere in Norway so i need to buy son new cylinders to match the new crank. but wht wil work best with the mods i alredy have? i do have 2 38mm airstrikers laying here. i want som good mid power and strong topend! 65, 68 or the supercub 72mm???? what will work best with what i alreay got??? Thanks for all coments!! Quote Link to comment Share on other sites More sharing options...
91banshee Posted December 29, 2007 Report Share Posted December 29, 2007 See my mods below, i want som more power and thinking of a 4mill crank. and cubs. there is no one that do port work hrere in Norway so i need to buy son new cylinders to match the new crank. but wht wil work best with the mods i alredy have? i do have 2 38mm airstrikers laying here. i want som good mid power and strong topend! 65, 68 or the supercub 72mm???? what will work best with what i alreay got??? Thanks for all coments!! your gona need a set of pipes , shearers or cpis for that cub a 4mil 68 bore 421 cub is a wicked motor . it will need those 38 carbs or 35s work well i ran mine stock trans set up with shift star and it shifted fine . also ran all 6 rdz springs to hold the clutch ,and i ran shearer inframes .you will need some serious tires for it to ,it will rip off knobs and roast a set of tires before you can even let off. the supercub reguires case boring and only makes about 5 more hp than the 68 and in imo its not worth the extra money it cost oh and it takes a diffrent head to . first thing i would get rid of is those fmf pipes . Quote Link to comment Share on other sites More sharing options...
Hilarious Posted December 29, 2007 Report Share Posted December 29, 2007 Yes, what Cam said. ^ You will also need new domes for your cool head and some bigger intakes for those bigger 38mm carbs. Once you have all the new horsepower, you'll need to be able to get it to the ground. So longer swingarm unless you like looking into the sky all the time. LOL :beer: Quote Link to comment Share on other sites More sharing options...
patarol Posted December 29, 2007 Author Report Share Posted December 29, 2007 (edited) Ok. thanks for helping out. I have a +4" swinger already, hope taht wil work. I wil try this setup. What crank to get, hotrod? are the FMF realy that bad for this setup? how mutch HP wil i lose with the FMF? whas hoping not to buy new pipes, but if it is a must i will. Edited December 29, 2007 by patarol Quote Link to comment Share on other sites More sharing options...
91banshee Posted December 29, 2007 Report Share Posted December 29, 2007 Ok. thanks for helping out. I have a +4" swinger already, hope taht wil work. I wil try this setup. What crank to get, hotrod? are the FMF realy that bad for this setup? how mutch HP wil i lose with the FMF? whas hoping not to buy new pipes, but if it is a must i will. [/quote dont run the fmf on a cub , wrong duration pipe . it is a must you buy a drag style inframe, yes i have tryed many pipes on a cub for kicks and fmfs will kill the cub and make it hard to jet .my personal recomindation would be shearer inframes next would be cpi Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted December 29, 2007 Report Share Posted December 29, 2007 Why not do a 4mill crank with your stock cylinders. A clean up port job on banshee cylinders doenst really compair to a dune port job or a 4 mill dune port job. Then you can get a set of CPI's or Shearer's then if it still isnt enough you can swap the cylinders out for a cub and you will alread have the pipes that a cub needs. josh Quote Link to comment Share on other sites More sharing options...
patarol Posted December 30, 2007 Author Report Share Posted December 30, 2007 Why not do a 4mill crank with your stock cylinders. A clean up port job on banshee cylinders doenst really compair to a dune port job or a 4 mill dune port job. Then you can get a set of CPI's or Shearer's then if it still isnt enough you can swap the cylinders out for a cub and you will alread have the pipes that a cub needs. josh Theres no one that can port the stok jugs to match the 4mil here in norway. There is a guy in sweden (www.ebos.com) that can do it but he charge 4500,- for the job so i need to buy cubs, and heard so mutc great about them to :biggrin: What crank should i buy? Quote Link to comment Share on other sites More sharing options...
patarol Posted December 30, 2007 Author Report Share Posted December 30, 2007 i will go for the CPI`s. big or smal bore pipes? for this 421 setup? and what crank do you recomend?? Thanks! Quote Link to comment Share on other sites More sharing options...
Hilarious Posted December 30, 2007 Report Share Posted December 30, 2007 i will go for the CPI`s. big or smal bore pipes? for this 421 setup? and what crank do you recomend?? Thanks! Small bore. Honestly, I would go with shearers over the CPIs for several reasons. The shearers pulled better on top end than the CPIs and the routing of the stingers around the air filters is wonderful. The CPIs just fit like crap on my bike. The downside tho, the chrome on the shearers is the worst I have ever seen. Id get a hot rods, long rod, 4mill stroker. It will drop right in. Anything bigger and you will have to get your cases machined. And if at all possible, have a builder re-weld it also. I have heard of numerous instances of people having them seperate. Good luck with your build. Quote Link to comment Share on other sites More sharing options...
patarol Posted December 30, 2007 Author Report Share Posted December 30, 2007 Small bore.Honestly, I would go with shearers over the CPIs for several reasons. The shearers pulled better on top end than the CPIs and the routing of the stingers around the air filters is wonderful. The CPIs just fit like crap on my bike. The downside tho, the chrome on the shearers is the worst I have ever seen. Id get a hot rods, long rod, 4mill stroker. It will drop right in. Anything bigger and you will have to get your cases machined. And if at all possible, have a builder re-weld it also. I have heard of numerous instances of people having them seperate. Good luck with your build. Ok thnks for the advice. did you men bad chrom on the CPI or shearers? Quote Link to comment Share on other sites More sharing options...
06BaNsHeE Posted December 30, 2007 Report Share Posted December 30, 2007 Ok thnks for the advice. did you men bad chrom on the CPI or shearers? I would call a builder first.My builder has send big motors all the way to australia.He will send them wherever you want.Also on the pipes Most builders now recomend BB Pipes on a 421 Cub.If you want call Nate Mccoy.1-530-476-2222.He does awesome work on cubs. Quote Link to comment Share on other sites More sharing options...
patarol Posted December 30, 2007 Author Report Share Posted December 30, 2007 I have read so mutch positiv about the CPI and shearers. so i only have to diside. the CPI are easier to get for me. so CPI it is. my build wil be this: 68mm cub, 38mm airstrikers, cpi inframe, 4mil crank + the small stuff i need for the build. see manny riders ride 421 set up and are realy happy with it, hope i will to. What will max HP be with this kind of motor?? Quote Link to comment Share on other sites More sharing options...
Wildcardracing Posted December 31, 2007 Report Share Posted December 31, 2007 I have read so mutch positiv about the CPI and shearers. so i only have to diside. the CPI are easier to get for me. so CPI it is. my build wil be this: 68mm cub, 38mm airstrikers, cpi inframe, 4mil crank + the small stuff i need for the build. see manny riders ride 421 set up and are realy happy with it, hope i will to. What will max HP be with this kind of motor?? Correct me if I'm wrong guys, but a 421 cub (unported) should be in the 70-80 HP range at sea level depending on setup. Quote Link to comment Share on other sites More sharing options...
06BaNsHeE Posted December 31, 2007 Report Share Posted December 31, 2007 with those mods on gas probably low 90s on a unported cub.Close to 100 if ported. Quote Link to comment Share on other sites More sharing options...
wesw Posted December 31, 2007 Report Share Posted December 31, 2007 you can ship stuff out like your jugs and have your local guy or yourself put it together. imo i dont think a cub would be the motor your looking for. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.